1. Field of the Invention
High-performance irrigator devices able to propel a water spray to a distance of between 10 and 100 meters are known in the irrigation field.
2. Description of the Prior Art
These spray irrigator devices, also known as impact irrigators, operate with a throughput up to 50 liters/second and a pressure up to 10 atm or 10.3323 kg/cm.sup.2.
One of the main problems of these machines is that they distribute the water jet poorly when below a certain pressure, so that the water jet, which remains undivided, causes serious damage to crops.
The best known irrigators have an internal profile which blends smoothly with the cross-section of the irrigator propelling tube at its outlet section, and although they offer the best results in terms of range, they operate properly with regard to atomisation and jet dispersion only above about 4 atm. or 4.13292 kg/cm.sup.2 pressure. This means that on start-up, the jet remains undivided until this pressure is reached, and excavates a groove in the soil.
To obviate this drawback, those delivery nozzles which have their internal profile smoothly blending with the cross-section of the propelling tube at the nozzle outlet section are generally associated with a jet breaker device in the form of a small cone or a point, which is inserted orthogonally into a small portion of the jet downstream of the jet outlet section.
In addition to constituting a definite constructional complication, the presence of this device is also damaging when the jet reaches normal operating pressure.
There is therefore a widely felt need for a delivery nozzle having a configuration such that it offers good jet dispersion starting from a pressure of the order of 2-3 atm. or 2.06648-3.0969 kg/cm.sup.2, in order to prevent crop damage.